Integrated intensity map of the ¹³CO(2−1) (top) and C¹⁸O(2−1) (bottom) transitions towards G341.246–0.267 in the velocity range of [−48.2,−41.0] km s^-1. Grey levels are from 10-σ (9.4 K km s^-1) for ¹³CO in steps of 10-σ, and from 5-σ (4.7 K km s^-1) for C¹⁸O in steps of 5-σ. The blue solid line marks the main spine of the filament identified; the magenta lines mark the other sub-branches identified on the ATLASGAL dust emission map by Li et al. (2016). The yellow empty circles mark the positions where the six spectra shown in Fig. 26 are extracted. The red thin line marks the dilation box used to compute the length and the mass of the filament.